Account (has_many :users)
    └── Feature Flag: allow_user_management
         └── Settings::UsersController
              ├── index (list team members)
              ├── new/create (add member)
              └── destroy (remove member, not self)

# Migration
add_column :accounts, :allow_user_management, :boolean, default: false, null: false

# app/controllers/settings/users_controller.rb
module Settings
  class UsersController < ApplicationController
    before_action :ensure_user_management_enabled
    before_action :set_user, only: [:destroy]

    def index
      @users = Current.account.users.order(:email_address)
    end

    def new
      @user = Current.account.users.new
    end

    def create
      @user = Current.account.users.new(user_params)
      if @user.save
        redirect_to settings_users_path, notice: t("settings.users.flash.create.success")
      else
        render :new, status: :unprocessable_content
      end
    end

    def destroy
      if @user == Current.user
        redirect_to settings_users_path, alert: t("settings.users.flash.destroy.self_delete_error")
        return
      end
      @user.destroy
      redirect_to settings_users_path, notice: t("settings.users.flash.destroy.success")
    end

    private

    def set_user
      @user = Current.account.users.find(params[:id])
    end

    def user_params
      params.require(:user).permit(:email_address, :password)
    end

    def ensure_user_management_enabled
      return if Current.account.allow_user_management?
      redirect_to settings_path, alert: t("settings.users.flash.disabled")
    end
  end
end

namespace :settings do
  resources :users, only: [:index, :new, :create, :destroy]
end